Add MDI icon picker to all entity types

- Install @mdi/js (~7000 Material Design Icons)
- IconPicker component: dropdown with search, popular icons grid,
  clear option. Stores icon name as string (e.g. "mdiCamera")
- MdiIcon component: renders SVG from icon name
- Backend: add `icon` field to ImmichServer, TelegramBot,
  TrackingConfig, TemplateConfig, NotificationTarget, AlbumTracker
- All 6 entity pages: icon picker next to name input in create/edit
  forms, icon displayed on entity cards

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/package-lock.json

@@ -7,6 +7,9 @@
 		"": {
 			"name": "frontend",
 			"version": "0.0.1",
+			"dependencies": {
+				"@mdi/js": "^7.4.47"
+			},
 			"devDependencies": {
 				"@sveltejs/adapter-auto": "^7.0.0",
 				"@sveltejs/adapter-static": "^3.0.10",
@@ -521,6 +524,11 @@
 				"@jridgewell/sourcemap-codec": "^1.4.14"
 			}
 		},
+		"node_modules/@mdi/js": {
+			"version": "7.4.47",
+			"resolved": "https://registry.npmjs.org/@mdi/js/-/js-7.4.47.tgz",
+			"integrity": "sha512-KPnNOtm5i2pMabqZxpUz7iQf+mfrYZyKCZ8QNz85czgEt7cuHcGorWfdzUMWYA0SD+a6Hn4FmJ+YhzzzjkTZrQ=="
+		},
 		"node_modules/@polka/url": {
 			"version": "1.0.0-next.29",
 			"resolved": "https://registry.npmjs.org/@polka/url/-/url-1.0.0-next.29.tgz",
@@ -2550,6 +2558,11 @@
 				"@jridgewell/sourcemap-codec": "^1.4.14"
 			}
 		},
+		"@mdi/js": {
+			"version": "7.4.47",
+			"resolved": "https://registry.npmjs.org/@mdi/js/-/js-7.4.47.tgz",
+			"integrity": "sha512-KPnNOtm5i2pMabqZxpUz7iQf+mfrYZyKCZ8QNz85czgEt7cuHcGorWfdzUMWYA0SD+a6Hn4FmJ+YhzzzjkTZrQ=="
+		},
 		"@polka/url": {
 			"version": "1.0.0-next.29",
 			"resolved": "https://registry.npmjs.org/@polka/url/-/url-1.0.0-next.29.tgz",